The present invention relates to a method for the preparation of a tert-hydrocarbyl silyl or a tert-alkyl silyl compound or, more particularly, to a method for introducing a tert-hydrocarbyl group directly bonded to a silicon atom in an organosilicon compound.
As a method for introducing a silicon-bonded tert-hydrocarbyl group into an organosilicon compound, a method is known in the prior art in which a tert-alkyl lithium is used (see, for example, Journal of Organic Chemistry, volume 43, page 3649, 1978 and Journal of the American Chemical Society, volume 76, page 1030, 1954). This method, however, is practically not applicable to the industrial production of such an organosilicon compound due to several disadvantages and problems that the tert-alkyl lithium is prepared in a process in which metallic lithium having a very high melting point of 190.degree. C. must be finely divided in a molten state into a fine particulate form having a particle diameter of a few .mu.m using a special apparatus while utmost care is essential in order to avoid any danger caused by the highly active metallic lithium and tert-alkyl lithiums may spontaneously catch fire when contacted with the atmospheric air so that handling of a large amount thereof is always accompanied by a great danger.
A general method for introducing a hydrocarbyl group into a silicon compound is the utilization of a Grignard reagent but this method is not applicable when the silicon compound to be reacted with the Grignard reagent is silicon tetrachloride, ethyl orthosilicate or an organosilane compound such as trimethyl chlorosilane so that no tert-hydrocarbyl-substituted silyl compound can be obtained from these silicon compounds (see, for example, Journal of the American Chemical Society, volume 70, page 2876, 1948).